Abstract: An electronic circuit, such as a UPS, interfaces a main ac power source and at least one secondary power source to a load. The secondary power source(s) may include one or more auxiliary generators, a flywheel motor generator or microturbine with high speed motor generator, and/or any of a variety of dc storage devices. The electronic circuit includes a dc bus, a first uncontrolled rectifier in combination with a first filter for coupling the main ac power supply to the dc bus, one or more additional uncontrolled rectifier(s) and filter(s) for coupling the auxiliary generator(s) to the dc bus, and a dc-to-ac inverter (between the dc bus and the load) for providing ac output power to the load. The advantages of reduced parts count, increased compatibility between the generator(s) and the electronic circuit, and a simpler method for paralleling many storage and generation devices with a very high power factor to the sources, regardless of the load power factor, are provided.

Abstract: Apparatus and method is disclosed for overcoming the voltage attenuation and ground shifts normally associated with providing DC power to distributed loads from a DC power supply without the need for excessively large conductors, the need to distribute the DC power supply or the need to provide converters at or near each load. Reasonably accurate voltage regulation at each load is provided according to the invention while using low but not insignificant resistance power conductors by providing similarly low resistance voltage sense conductors. The loads are connected between the sense conductors in a distributed fashion. Current approximating that drawn by each load is injected from the power conductors to the sense conductors at or near each load. Dynamic current requirements are supplied by capacitors connected across each load, usually mounted on the load circuit boards.

Abstract: In a computer system in which adapter cards can be “hot plugged” into an I/O bus connector, a serially connected resistor and “voltage feedback” switch is coupled between the power supply pin of each I/O connector and the power supply input port that regulates the voltage at the output port of the power supply. Another resistor, which has a resistance greater than each of the resistors coupled to the I/O connectors, is connected between the input and output ports of the power supply to provide voltage feedback to regulate the output voltage of the power supply in the event that power to all of the I/O connectors is switched OFF. The power to an individual I/O connector is turned OFF before an adapter card is plugged into or removed from an I/O connector, and the power is turned ON immediately after the card is plugged into the connector.

Abstract: A circuit to control the supply of a reactive load, for supplying variable quantities of energy to the load in a predetermined manner is included in a system. The system also includes reactive components which are connected to the load by way of a controllable electronic switch and which form a resonant circuit with the load when the electronic switch is closed. Further, the system includes a circuit for activating the electronic switch, and a control unit which coordinates the operation of the controlled supply circuit and of the activation circuit in accordance with a predetermined program. The system enables the load to be driven with a particularly low power dissipated.

Abstract: A discharge gap device which is provided between an antenna input terminal or a secondary side earth and a commercial power source, or between the power lines of a commercial power source as a ground discharge countermeasure for electrical equipments such as a television set, a video cassette recorder, and a television and video compound device. The discharge gap device functions only as a discharge gap unit and has two conductors. Normally, the conductors are not electrically connected to each other, and upon application of over-voltage, discharge occurs between the conductors; that is, the conductors are electrically connected to each other.

Abstract: The switching functions of switching a load on and off in normal operation and in fault operation are implemented in a simple manner in an electronic branch circuit switch, which is advantageously made with silicon carbide semiconductor switching elements and has a potential-free control device, a device for detection and immediate shutoff in the event of a short-circuit, and a protection device for detection and shutoff against overload currents, as well as an overvoltage limiting device.

Abstract: An electrical system for use in isolation, the electrical system comprising a main engine (14), such as a gas turbine or a diesel engine, a generator (13) driven by the main engine (14) for generating a first alternating voltage (19), a first rectifier unit (12) for converting the first alternating voltage (19) generated by the generator (13) into a direct voltage on a DC bus (18), and at least one inverter unit (10, 15) for converting the direct voltage of the DC bus (18) into a second alternating voltage (20). The generator (13) driven by the main engine (14) for generating the first alternating voltage (19) is an asynchronous machine coupled directly to the shaft of the main engine (14), and the first rectifier unit (12) also comprises an inverter part for converting the direct voltage of the DC bus (18) into an alternating voltage with an adjustable frequency to said asynchronous machine (13) so as to use the machine as a motor.

Abstract: A low cost voltage disturbance mitigation system is capable of providing continuous power to a load despite short interruptions or sag disturbances of the utility power. The interruption and sag mitigation system makes use of a combination of unique thermal and electrical properties of magnetic components, power semiconductor devices, and high-discharge-rate energy storage devices. It also facilitates a modular solution that can be easily and economically scaled up or down for use over a wide range of voltage and power levels, e.g., 480 V to 36 kV and 500 kVA to 10,000 kVA.

Abstract: A module is provided which includes two gas-filled surge arresters arranged next to one another in a housing. An auxiliary discharge gap and a short-circuit device is associated with each surge arrester. One side of each surge arrester is in contact with a plate, which forms the ground, as well as the stationary electrode of the short-circuit device. On the other side, the plate is in contact with two varistors which form the auxiliary discharge gaps. A cap, forming the movable electrode of the spring-loaded short-circuit device is placed on each varistor with a meltable spacer between them.

Abstract: Methods for the ready identification of dynamic defects using switching induced light emission from CMOS gates in complex integrated circuits such as microprocessors are described. The rapid increase in the complexity of logic circuits means that practical gate level identification of the sources of dynamic errors will require methods other than the gate by gate tracing of every possible path taken by a given set of instructions. The methods described here are based on the ability of picosecond imaging circuit analysis to detect the switching activity of every gate of a complex circuit in a single, passive measurement, and the ability of data processing today to compare large two- and three-dimensional files.

Abstract: A power supplying adapter which is connected to an AC power source and generates a predetermined DC voltage is constructed by a power supplying unit in which a small power mode to output a small electric power and a large power mode to output a large electric power can be switched; a current detecting unit for detecting a current outputted from the power supplying unit; a signal receiving unit for receiving a signal transmitted from electronic equipment; and for control means for making the power supplying unit operative in the small power mode and making the signal receiving unit means operative when the current detected by the current detecting unit is equal to or smaller than a reference value. The electronic equipment is constructed by a signal transmitting unit for transmitting a signal to the power supplying adapter; a second control unit for controlling the signal transmitting unit; and a switching unit for switching a power source which is supplied from the power supplying adapter.

Abstract: A mobile X-ray machine includes an improved Marx generator. The capacitors sed in the Marx generator are disc capacitors each having opposed side surfaces having electrodes formed thereon and each including a insulative coating provided on the peripheral edge thereof. The capacitors are mounted in slots in a support structure and are supported by spring contact members located within the slots. The spring contact members include spring arms which engage the electrodes on the opposed side surfaces of the associated capacitor. The spring contact members also include support elements from which are suspended the spherical electrodes of spark-gap switches individually associated with each of the capacitors.

Abstract: A patch cord and method for installing new hardware in a remote terminal of a telecommunications system. Hardware installed inside remote terminal cabinets require lightning protection systems to prevent damage from sudden power surges. The patch cord and method allow new hardware to be installed in the remote terminal using existing lightning protection systems.

Abstract: The invention specifies a disconnector for decoupling a load from a supplying AC voltage network. The disconnector comprises at least one disconnector stage having a series circuit comprising at least two reverse-conducting gate turn-off thyristors which are connected cathode to cathode. The gate turn-off thyristors are preferably hard driven. This allows the use of a single circuit capacitor in parallel with the series-connected gate turn-off thyristors. This embodiment has the advantage that, during disconnection, the current commutates early from the gate turn-off thyristors, which means that the disconnection capacity can be increased.

Abstract: A modular power supply which distributes responsibility for supplying current to a load among two or more power supply modules having a common output node. One of the power supply modules which supplies the lowest level of current to the load functions as the master while the remaining power supply modules each function as a slave. A load share bus which interconnects all the power supply modules is driven by the master with a signal representative of the level of current supplied by the master. Each slave module attempts to reduce its output current to a level which is a predetermined offset above the level of current supplied by the master while a regulated voltage is maintained at the common output node. Any one of the modules can become the master, though once the system is operating, the predetermined offset generally prevents the roles from changing. Should one of the power supply modules fail such that its output current is uncontrolled, this power supply module will not be the master.

Abstract: A protector cartridge circuit arrangement which permits more robust line protection. The circuit arrangement has high-capacity and large-sized components staggered across the surface of a printed circuit board such that high-capacity components can be used in the cartridge to protect plural, adjacent lines. Such devices cannot be used in pair-at-a-time protectors because of space constraints. A preferred industrial application is the protection of communication lines.

Abstract: An electrical junction box for a vehicle includes a housing and a circuit disposed in the housing for receiving power from a remote power source. At least one power switching device is electrically connected to the circuit for switching power from the power source to a remote electrically-actuated device in the vehicle. A controller operates the at least one switching device. The junction box is characterized by the controller being removably connected to the circuit. In a first version, the controller is packaged in a protective case separate from the junction box housing. In a second version, the controller is accessibly packaged within the electrical junction box housing. Both embodiments accomplish one object of the present invention to provide a controller for an electrical junction box which is easily and quickly removable for service repair or replaceable for micro-processor chip upgrade.

Abstract: An overvoltage and transient protection circuit with extended bandwidth is provided for the protection of a low voltage test signal path (210) such as a test signal path in a multimeter. The disclosed circuit maintains the integrity of a test signal (TS) (114) transmitted by the test signal path (210) by minimizing the effect that unwanted capacitive coupling would otherwise have on the frequency transmission capability of the circuit. During normal operation of the circuit, a test signal path isolation circuit (218) is held between the test signal (TS) (114) and an equivalent buffered guard signal (GS) 227. Held between these equivalent values (TS=GS), no (or minimal) current will be generated in the components of the test signal path isolation circuit (218) as a result of parasitic capacitance. The guard signal (65) (227) is used with guard traces (412) and guard planes (414) to isolate other parts of the test signal path in much the same way.

Abstract: A power supply circuit for AC/DC adapter-powered or battery-powered portable electronic devices, which has a linear regulator, and includes a voltage level adjusting circuit coupled to the linear regulator. The voltage level adjusting circuit lowers a voltage supplied from the AC/DC adapter to a predetermined level. In an embodiment, the level-adjusted voltage equals a voltage supplied from the battery. The linear regulator is therefore always provided with a constant voltage regardless of the power sources.

Abstract: A method and apparatus for providing standby power from a generator. The method and apparatus includes determining a power failure condition of a primary power source, disconnecting the primary power source from a load, connecting the generator to the load, connecting a first capacitor supplied voltage to a starter system, activating the starter system to start the generator, and providing a second capacitor supplied voltage to a capacitor monitor/diagnostics controller during a transition period between the primary power source and the generator standby power.